1. Field of the Invention
The present invention relates to quick connect tube couplings, and more particularly to improvements in configurations for such couplings.
2. Description of the Related Art
Quick-connect tube couplings are used to connect flexible tubes in fluid power systems such as, for example, pressured air systems for vehicle air brakes and air conditioning systems, which may involve connections to diverse items such as valve bodies, air tanks and the like. In these and other systems, each flexible tube requires a coupling to connect the end of the tube to a body, such as a conventional fitting, valve, manifold or similar device for transmitting and receiving pressurized fluid. Connecting a tube to a body, or removing a tube from a body, can be a time consuming and expensive task that is frequently performed in the field where specialized tubes may not be readily available.
There are a variety of “push-to-connect” type couplings that permit a tube to be quickly and easily connected to a valve or manifold body without the use of tools. With these couplings, a tube is connected by simply press-fitting the coupling into a bore within the body and then inserting the leading end of the tube into the coupling. Typically, the coupling contains a plurality of components that releasably retain the tube therein.
One known quick-connect coupling design includes a sleeve with a tube support mounted therein, an internal O-ring, an external O-ring and a collet that cooperatively retain the tube on the tube support by engaging the tube with the collet. While this design has proven effective in practice, coupling designers continue to develop improvements in these types of couplings to further minimize manufacturing expense, reduce assembly errors and expedite assembly of the components prior to insertion into a fitting or manifold body.